How to fix the Oracle error ORA-12500: TNS:listener failed to start a dedicated server process?

In this post, you’ll learn more about the Oracle ErrorORA-12500: TNS:listener failed to start a dedicated server process with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-12500: TNS:listener failed to start a dedicated server process

Reason for the Error ORA-12500: TNS:listener failed to start a dedicated server process

The process of starting up a dedicated server process failed. The executable could not be found or the environment may be set up incorrectly.

How to fix the Error ORA-12500: TNS:listener failed to start a dedicated server process ?

You can fix this error in Oracle by following the below steps

Turn on tracing at the ADMIN level and reexecute the operation. Verify that the ORACLE Server executable is present and has execute permissions enabled. Ensure that the ORACLE environment is specified correctly in LISTENER.ORA. The Oracle Protocol Adapter that is being called may not be installed on the local hard drive. Please check that the correct Protocol Adapter are successfully linked. If error persists, contact Oracle Customer Support.